On Tue, 1 Jul 2014, Russell King wrote: > ARMv6 and greater introduced a new instruction ("bx") which can be used > to return from function calls. Recent CPUs perform better when the > "bx lr" instruction is used rather than the "mov pc, lr" instruction, > and this sequence is strongly recommended to be used by the ARM > architecture manual (section A.4.1.1). > > We provide a new macro "ret" with all its variants for the condition > code which will resolve to the appropriate instruction. > > Rather than doing this piecemeal, and miss some instances, change all > the "mov pc" instances to use the new macro, with the exception of > the "movs" instruction and the kprobes code. This allows us to detect > the "mov pc, lr" case and fix it up - and also gives us the possibility > of deploying this for other registers depending on the CPU selection. > > Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> For the Xen changes: Acked-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx> _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm